Mode proximity and frequency response of push-pull DFB lasers

Summary form only given. Single-mode DFB semiconductor lasers with wide modulation bandwidth and low frequency chirp are highly desirable for high-speed and long-haul optical telecommunication systems. The recently proposed push-pull DFB lasers have displayed many promising features for progress in that direction. Numerical work alone can not give sufficient insight in device operation. Using the spatially-dependent multimode rate equations for the modal field amplitudes we study for the first time analytically the AM and FM response and resonance frequency lasers. The formalism includes essential features such as longitudinal spatial hole burning, nonlinear gain compression, and sidemode contribution rigorously.